Alternating-current generator.



H. DE F. ARNOLD. ALTERNATING CURRENT GENERATOR, APPLICATION FILED JUNE 12, 1913, I 1,1 18 5174. "Patented Nov. 24, 1914-.

' Erma-sum 1.

H. DE F. ARNOLD.

ALTERNATING CURRENT GENERATOR.

APPLICATION FILED JUNE 1 2. 1913.

1 1 1 8, 1 74. Patented Nov. 24, 1914.

2 SHEETS-SHEET 2.

UNITED s'rATEs PATENT union.

HAROLD DE FOREST ARNOLD, OF EAST ORANGE, NEW JERSEY, ASSIGNOR- TO WESTERN ELECTRIC COMPANY, OF NEW YORK, N. Y., A CORPORATION OF ILLINOIS.

ALTERNATING-CURRENT GENERATOR.

Specification of Letters Patent. Patented Nov. 24, 1914;

. Application filed June 12, 1913. SeriaINo. 773,269.

To all whom it may concern:

Be it known that I, HAROLD DE Fonns'r ARxoLD, a citizen of the United States, residing at East Orange, in the county of Essex and State of New Jersey, have invented a certain new and usefullmpmvement in Alternating-Current Generators, of which the following is a full, clear, concise, and

exact description.

This invention relates to a device for generating undamped high frequency electrical alternations or oscillations. Where oscillations of this character are desired, it is usual to utilize the free oscillations which may occur in a circuit containing capacity and inductance. In a circuit of this character, containing the usual condenser and inductance coil, oscillations may be generated employ a source or generator of high fre-v quency oscillations which will produce sustained and undamped oscillations.

It is an object of this invention to produce such a generator. lVith this object in view, in addition to the usual oscillatory circuit containing capacity and inductance, an auxiliary circuit is employed, the object of the auxiliary circuit being to supply energy to the oscillatory circuit and thus prevent the damping of the -oseil1ations. These two circuits may be connected in multiple, or they may be inductively connected. In order that the energy may be supplied to the oscillatory circuit inthe proper increments and at proper intervals, a part of the auxiliary circuit consists of a field of ionized vapor which is acted upon magnetically by the oscillations in the oscillatory circuit. Preferably the field of ionized vapor is produced by an arc discharge in an evacuated tube containing mercury vapor, such are discharge being maintained by a circuit through the gaseous medium produced thereby independent of both the oscillatory and auxiliary circuits above referred to. It is obvious that any suitable source of ionization could be used instead of the mercury are, as the means for producing such ionization is entirely inde pendent of the rest of the apparatus.

v The invention will be more fully understood by reference to the accompanying drawings wherein Figure 1 is a view showing the apparatus and circuits comprising one form of the alternating current generator of the invention. F1 gs. 2 to 4 are views showing modifications of the apparatus andcircuits of Fig. 1.

Referring to the drawings, in the particular embodiment of the invention illustrated, a mercury arc device is employed for the purpose of producing a field of ionizedv vapor. This device comprises an evacuated glass receptacle having a main chamber 1 with a horizontal branch 2, and a condensing chamber 3, together with a mercury cathode et, an anode 5 of carbon or other suitable material, and a starting mercury anode 6. Supported within the main chamher 1 in the form of the device shown in Figs. 1 and 4, are a pair of auxiliary electrodes 7 and 8, which are shown semi-cylindrical in form and slightly separated from each other and from the walls of the chamber.

In the form of the device shown in Figs.

2 and 3, three auxiliary electrodes 9, 10 and 11 are supported in the main chamber 1. Two of these elctrodes 9 and 10, are similar in construction to electrodes 7 and 8 hereinbefore described. The third electrode 11 extends from the Wall of the chamber. 1 downwardly between the electrodes 9 and 10. Embracingthe main chamber 1 adjacent the auxiliary electrodes, is an electromagnet 12, thagneans oflsupport of which is not shown." Such magnet comprises a pair of coils 13, 14.- surrounding inwardly extending pole pieces, the outer ends of which are joined by a yoke piece 15. The pole pieces are so arranged that the magnetic lines of force between them are in a direction transverse to the flow of the ionized stream in the I chamber 1. The magnet construction is the same in all four figures and serves to alter the distribution of ionization between electrodes 7 and 8 or 9 and 10 as the case may be.

Also in all four forms of the invention a ance 17 and resistance 18.

which is connected to the anode 5, and the negative pole of which is connected to the mercury cathode 4 through a balancing or steadying impedance comprising an induct- An auxiliary decrease in the current in such circuit. Thus at the time when a pulsation is approaching its maximum value, the corresponding oscillation is approaching its maximum positive value, and when a pulsation is approaching its minimum value, the corresponding oscilonly one battery is employed. In this form 7% starting circuit, including a starting key 42 lation is approz-iching its maximum negative is provided. The mercury arc circuit, when value so that in either case the impulsetends once established, as by tipping the tube, closto sustain the oscillation and prevents the ing the circuit at the starting key 42 over the damping thereof.

path 16,17, 18, 4,2, 1, 6, 42, 16 and then re In the modified arrangement shown in 75 leasing the key 42, is maintainedautomati- Fig. 2, the electrode 11 is connected to the cally over the path 16, 17, 18, 4, 2, 1, 5, 16, positive side of'the battery 24 and hence which includes the ionized stream in the acts as an anode. The electrodes 9 and 10 main chamber 1. I are connected to the negative side of the bat- Referring to the form of the inventiontery through retardation coils and 26. shown in Fig. 1, the oscillatory circuit corn- In this case the auxiliary circuit has two prises the magnet coils 13 and 14, an adjustbranches, both of which include a portion of able inductancecoil 19 and a condenser 20. afield of ionized vapor. The oscillatory cir- As this circuit contains both inductance and cuit, which comprises the condenser 46, the capacity, it fulfils the conditions necessary primary coil of the transformer 27 and the for the production of high frequencyoscilmagnet coils 13 and 14, is bridged across the lations, and by making the inductance 19 negative electrodes or cathodes 9 and 10. or the condenser 20 adjustable, the natural When the arc is deflected toward one of the V period of the circuit and hence the frequency cathodes it is deflected away from the other of the oscillations may be varied. The auxcathode, which results in an increase in the iliary circuit comprises the battery 21, the current in one branch 0f the auxiliary cirinductance coil 22, which is wound on the cuit, and a corresponding diminution in the same core as the coil 19, and in connection other branch. The oscillatory circuit being with such coil serves to inductively connect connected across the twobranches of the auxo the oscillatory and auxiliary circuits, the iliary circuit, the sum of the variations ln electrodes 7 and 8, and the ionized vapor such branch circuits is impressed upon the therebetween. By means of the transformer oscillatory circuit. The operation of" the 23 in the oscillatory circuit, the oscillations generator shown in Fig. 2 is similar to that produced therein may be utilized in a'supof the generator of Fig. 1 with the exception ply circuit for wireless telegraph or telethat, owing to the divided circuit arrangephone or other apparatus. When the genment of the aux liary circuit, double the erator is in operation, an arc is maintained effect of the auxiliary circuit upon the oscilbetween the anode 5 and the cathode 4. This latory circuit is obtained.

,. arc is maintained constant and the intensity The generator shown in Fig. 3 is like that thereof is independent of either the oscilshown in Fig. 2 with the exception that the latory or auxiliary "circuits. Thearc above auxiliary circuit, instead of being connected referred to provides a field of ionized vapor directlyacross the electrodes 9 and 10, is inbetween the electrodes 7 and 8, which .field ductively connected in substantially the is acted upon by the electromagnet 12 same relation by means of a transformer.

in the oscillatory circuit. When the oscil- Referring to Fig. 3, the oscillatory cir- 11 lations are started in the oscillatory circuit comprises the magnet coils 13 and 14, cuit, as, for instance, by discharging the the primary coil of the transformer 28, the condenser 20, such oscillations, passing condenser 29 and the ad ustable inductance through the coils 13 and 14, act upon 001130. The anode 11 is connected to the the field of ionized vapor between the elecpositive pole of the battery 31 and the cathn5 1 trodes 7 and 8, serving to vary the disodes 9 and 10 to the negative pole through tribution of the ionization between such electhe retardation co1ls 32 and 33, respectively. trodes. In the arrangement shown in Fig. Bridged across the cathodes 9 and 10 is a 1, one of the electrodes which is connected circuit includ ng the condenser 34 and the to the negative battery acts as a cathode. It inductance C011. 35. By means of the coils has been found by experiment that When the 30 and 35,- wh 'ch are wound on the same are is deflected by the magnet toward the core, the auxiliary and oscillatory circuits cathode, there is an increase in the current are inductively connected.

in the auxiliary circuit, and a deflection in In the form of generator shown in Fi ithe other direction causes a corresponding 4, a circuit arrangement is used in whici seated, it has been found that, substantially,

the main anode 5 acts both as the anode for the main arc stream, and as the anode for the auxiliary circuit. The auxiliary circuit has two branches which may be traced 1 3. ulsations the auxiliary circuit are caused the oscillations in the oscillatory circuit. GzASQthese two circuits are inductively conas follows: From positive battery 16, anode 5, cathode 7, inductance coil 36, retardation coil 37 to negative battery, and from positive battery 16, anode 5, cathode 8, inductance coil 38, retardation coil 37 to negative battery. The oscillatory circuit comprises the magnets 13 and 14, the primary coil of the transformer 39, condenser 41 and the adjustable inductance coil 40. Asthe coils 36, 38 and 40 are wound on the same core,

, such coils provide an inductive connection auxiliary circuit cooperating therewith and including auxiliary electrodes immersed in said ion zed vapor, and means for varying the conductivity between said auxiliary electrodes, such variations acting to add,incre-' ments of energy to said oscillatory circuit. 2. In an alternating current generator, an

oscillatory circuit, means for maintaining a field of ionized vapor, an auxiliary including a source of energy and a lionarcing current path through said vapor and' means for varying the conductivity of said current path, and by virtue of such varia- J tions adding increments of electrical energy to the oscillatory circuit.

In an alternating current generator Ya vapor electric device, means, tor maintalning an ionized are stream therein, an oscillatory circuit, an auxiliary circuit cooperating therewith and comprising electrodes immersed in said are stream, and means included' in said oscillatory circuit adjacent said electrodes for varying the electrical conductivity between said electrodes, whereby sustained electrical oscillations-are produced in said oscillatory circuit. a

4. In an alternating -current generator, means for maintaining a field of ionized vapor, an oscillatory circuit, an auxiliary circuit cooperating therewith, comprising a source of energy and-a current path through said ionized vapor and means included in said oscillatory circuit and responsive to the oscillations therein for varying the conductivity of said ionized vapor, thereby producing energy pulsations in the auxiliary circuit, said pulsations acting to reinforce the oscillations in the oscillatory circuit.

.5. In an alternating current enerator,

an evacuated receptacle, means, or maintaining a field of ionized vapor therein, an

oscillatory circuit, an auxiliary circuit comprising a source of energy and electrodes immersed in saidionized vapor, means responslve to oscillations 1n sa1d osc llator'y circuit acting upon the ionized vapor for producing energy pulsations in the said auxiliary circuit, said pulsations acting to reinforce the oscillations in the-oscillatory circuit. Y

In witness whereof, I hereunto subscribe my name this tenth day of June A. D., 1913.

' HAROLD DE FORESTABNOLD.

Witnesses:

James W. FARRELL, MURRAY V: CONATY. 

